This invention relates to a seal arrangement, and more particularly, to a seal arrangement for use in a track joint of the type used in a track chain on crawler tractors.
The prior art is already aware of various arrangements of track joints for crawler tractors, and those joints typically include separate thrust rings and seal rings. The purpose of such joints is to have a sturdy joint which is sealed against the entry of dirt and the like so that the joint can remain clean and functional with only a minimum of friction and wear. Examples of the prior art utilizing a rigid thrust ring and a separate elastomer seal member or the like are found in U.S. Pat. Nos. 3,841,718 and 4,030,730 and 4,062,550 and 4,094,516 and 4,195,852 and 4,204,716 and 4,209,204.
In my U.S. Pat. No. 4,204,716, assigned to the assignee of this invention, a highly effective seal arrangement for a track link is disclosed. As shown therein, the seal arrangement includes a thrust ring and a seal ring secured thereto. The two rings extend in axial abuttment between two annular surfaces presented by the track joint. Thus, in that instance, the thrust ring maintains the annular surfaces spaced apart, and the seal ring is effective between those annular surfaces to preclude the entry of foreign material, such as dirt and dust, and thus the joint is stable and secure and it is also kept clean.
The present invention is an improvement on the seal arrangement of the general type disclosed in U.S. Pat. No. 4,204,716. Among the objectives of the invention is to provide a seal arrangement which includes means for axially and radially loading the sealing leg portions, while maintaining the leg portions in tension so as to provide sufficient load and memory when installed in a predetermined operating width or confining space. Another objective is to provide such a seal arrangement which eliminates the need for a separate seal thrust ring and provides one-piece symmetry for easy installation.